Quick-lift pump



M. N. GRIFFIN AND R. E. GEORGE.

' QUICK LIFI PUMP. I APPLICATION FILED JUNE 26, I919- 1,41 7,317 P ented May 23, 1922.

srnns Filti'fil i i enromnrr'r PUMP.

Lei "2,317.

Application filed June as,

To aZZ whom it may concern:

Be it known that we, Monrmnr: N. GRIF- FIN and RUGAR E. Gnome, citizens of the drive-shatt 2.

United States, residing at Rome, in the county of Floyd and State of Georgia, have invented certain new and useful Improvementsin QuileLift Pumps, of which the :t'ollowingis a specification.

Our invention relates to an improvement in a quick lift pump, with automatic cut-out, and adapted more particularly for use in connection with the regular pumps on hydraulic direct lift presses, and the present invention is, in reality, an auxiliary pump operated in connection with the two high pressure pumps of such a press.

The present invention comprises a pump with a double plunger, the inner of which takes the initial power, and the other of which handles liquid in connection with a spring which controls the pressure within the outer plunger, said spring bearing on the bottom of the inner plunger, so that when pressure has reached the maximum strength of the spring, the movement of the outer plunger will he stopped, and the inner plunger will continue to travel, thereby compressing and expanding the spring at each stroke of the inner plunger. thus making an automatic cut-out for the pump without any cessation in the movement of the initial power.

In the accompanying drawings Fig. 1 is a view in perspective of the end of a press showing our improvement attached thereto;

Fig. 2 is an enlarged view in side elevation; and

Fig. 3 is a section.

A, represents a'push-rod connection which extends from the center eccentric 1 on the B is an auxiliary plunger connected to the push-rod by: a pin 3 ex tending through the hole 4. C, is the main plunger, and D, is a pump-barrel. The aux- :iliary plunger B is fitted within the bore of the outer plunger C, as clearly shown in Fig. 3, the inner plunger B taking the initial power while the outer plunger C handles the liquid in the barrel D. G, is the suction line leading from the tank.

A spring 6 located in the bore of the outer plunger C bears against the bottom of the latter, and the inner end when plunger B 1s as shown in Fig. 8, and when pressure has reached the maximum strength of this Specification of Letters Patent.

Fatented Ziiay 23, 1922. 1919. Serial no. 308,905.

spring the outer plunger C will strike the stop-bracket E projecting outwardly from the press 8 and stop moving, as shown in Fig. 2, the collar 9 being secured on the up per end of the outer plunger C "for that purpose, and the inner plimgcr B will continue to travel, it being provided with the grooves 10. These grooves extend longitudinally thereof, and into them the pins 11 er:-

tend from the collar 9, they being held in v position by the set-screws 12. shown in Fig. 3. This continued travel of the inner plunger results in the compression and expansion of the spring (3 at each stroke of the inner plunger, thereby making an automatic cut-out for the pump without stopping the movement of the initial power.

F, represents a check-valve located in the pipe 13 leading from the barrel D. H is the discharge pipe line (see Fig. 1) from the auxiliary pump, as well as from two high pressure pumps I which are connected to the discharge pipe H by the pipes K.

The action of the pump is as follows:-

Plunger C is preferably bored out to a depth of about ten inches, and the coil-spring 6 inserted therein, and between its bottom and the end of the inner plunger B is of suiiicient strength, to withstand a pressure of sixty pounds per square inch on plunger C. When the pressure on plunger C increases to a point above sixty pounds, the plunger will stop at the top of its stroke and bear against stop-bracket E, and remain there while plunger B continues to travel, compressing and releasing spring 6 at each stroke. This makes a positive cut-out for the'low pressurepump and makes is unnecessary to employ any troublesome automatic valves, the idea being that all three pumps will handle the liquid until the pressure in the cylinder of the press has reached a maximum of sixty pounds per square inch, when the plunger C will stop at the top of its stroke, thereby stopping the action of this pump, and the high-pressure check-valve marked F will hold the liquid pumped out of the pumpbarrel D, and the two smaller pumps I will build up the pressure necessary for the final operation of the press.

We claim:

1. In a hydraulic press, the combination with high pressure pumps, of an auxiliary pump comprising an inner and outer plunger having a spring interposed therebetween, and a barrel to the bore of which the outer plunger is fitted, a stop for the outer plunger, a check-valve, and pipe lines for the,

several pumps.

2. In a hydraulic press, the combination of high-pressure and auxiliary pumps, pipelines therefor, the auxiliary pump comprising a barrel and an inner and outer plunger with interposed spring, the outer of which. plungers is fitted to the bore of the barrel, means for limiting the stroke of the outer plunger, and a check-valve connected with the barrel.

3. The combination with a hydraulic press, and pumps and pipes there'l'oigoil" an auxiliary pump, comprising a barrel and an inner and outer plunger with an interposed spring, a discharge pipe line connecting all three pumps, a check-valve in the pipe leading from the auxiliary pump, and means For stopping the outer plunger in the auxiliary pump when the pressure in the cylinder of the press has reached a certain point, thereby stopping the action of the auxiliary pump, the check-valve holding the liquid pumped out oi. the pump, while the highpressure pumps will continue to build up the pressure necessary for the final operation of the press.

4. The combination with a hydraulic press, of two highpressure pumps and an auxiliary pump, the auxiliary pump having an inner and outer plunger fitted to operate one within the other, a barrel in which the outer plunger operates, a spring interposed between the inner and outer plunger, and means for stopping the outer plunger when a predetermined pressure has been reached in the cylinder of the press. a Y

5. The combination with a hydraulic press, and aishaft having a plurality of leccentrics thereon, of high-pressure pumps and an auxiliary pump all operated from the Y plurality of eccentrics on the shaft, theauxiliary pump having an inner and outer plunger fitted to operate one within the other, a barrel in which the outer plunger operates, a spring interposed between the inner and outer phinger, and means for stopping the outer plunger when a predeterminedpressure has been reached in thecylinder of the press.

In testimony whereof we aiiix our signa tures. 

